(P-TS-62) Outpatient Transfusions and Transfusion-Related Acute Lung Injury (TRALI) Among U.S. Medicare Beneficiaries, Ages 65 and Older, During 2016-2022

Background/Case Studies: Transfusion-Related Acute Lung Injury (TRALI) is a leading cause of transfusion-related fatalities. The study assessed TRALI occurrence, severity, and potential risk factors among fee-for-service Medicare beneficiaries, aged 65+, transfused in the institutional outpatient setting from 2016-2022.

Study

Design/Methods: This retrospective study used Medicare databases with procedure, revenue center, and diagnosis codes to identify outpatient transfusions and TRALI occurrence on the same or next day of transfusion. Unadjusted TRALI rates per 100,000 transfusion visits and 95% CIs were evaluated: overall, annually, pre-pandemic (Apr 2016-Dec 2019), during COVID-19 pandemic (Jan 2020-Dec 2022), and by immunocompromised (IC) status, recipient and transfusion characteristics. Severity measures included hospitalization, ICU admission, length of stay (LOS), and inpatient mortality.

Results/Findings: Of 2,990,541 outpatient transfusion visits, 146 had TRALI recorded; an overall rate of 4.9 (4.2-5.7): 5.4 (4.4-6.6) pre-pandemic vs. 4.2 (3.2-5.5) during pandemic. Table 1 shows TRALI rates by recipient and transfusion characteristics. Of TRALI cases, 62.3% were hospitalized with 71.4% ICU admission, 37.4% LOS≥7 days and 18.7% inpatient mortality.

Conclusions: Overall, results suggest TRALI to be a severe event among outpatients due to high case hospitalization rate post transfusion. This study identified lower TRALI rates during pandemic and found higher rates for non-IC vs. IC, males vs. females, whites vs. non-whites, and with more units transfused. In contrast, TRALI rates declined with advancing age. The findings suggest differential impact of blood components, processing, and patient comorbidities, and highlight utility of real-world evidence.

Importance of research: The study utilized large real-world Medicare data to assess TRALI occurrence, severity, and potential risk factors among fee-for-service Medicare beneficiaries, aged 65+, transfused in the institutional outpatient setting during 2016-2022. It assessed TRALI occurrence before and during the COVID-19 pandemic, and by demographics, blood components, and immunocompromised (IC) status to better understand trends and risk factors and help assure transfusion safety.